New polycatenar liquid crystals containing two 1,3,4-oxadiazole rings interconnected by a bent 1,3-substituted benzene ring as the central linking unit and three alkoxy chains at each terminal have been synthesized and investigated by polarizing microscopy, DSC, XRD scattering, UV-vis spectroscopy and photoluminescence measurements. All compounds form enantiotropic hexagonal columnar phases and have broader mesophase ranges than the corresponding para substituted analogues and show strong blue fluorescence emission with a large Stokes shift in solution.

Target compounds can self-assemble into a thermotropic LC phase sequence of SmC–Col_hex–Cub_I and have binding selectivity to Cu²⁺.

The first examples of unsymmetric coumarin polycatenar liquid crystals consisting of a coumarin central core with 1,2,3-triazole dendritic wings on both sides were synthesized via click reaction. Their properties were investigated using POM, DSC, XRD, SEM, IR, UV-vis spectra and photoluminescence measurements. Such polycatenars can self-assemble into different columnar liquid crystalline phases ranging from p4mm via p2mm to p6mm in their bulk states and into organogels with nanobelt or porous morphologies in different solvents. These polycatenars can exhibit highly fluorescent emission with large Stokes shifts (90–118 nm) in solution and as films. Most interestingly, the photodimerization in both LC and non-LC phases led to the formation of absolutely hexagonal columnar LC phases, while photodimerization in gel states led to the formation of flowerlike or 3D porous morphologies. Either columnar phases or gels with flowerlike or ordered porous morphologies were first observed in coumarin based derivatives.